Answer :
Answer: 3P/2
Explanation: Let the resistance of the bulbs be R.
now lets consider a Voltage V is supplied to the parallel circuit such that
[tex]P=VI=V^2/R[/tex]
V=IR
both single bulb( bulb 3) and the two bulbs ( bulb 1 and bulb 2) are provided the same Voltage
( as the voltage remains same in parallel circuit)
we can calculate the Current across both circuits
At Bulb 3
Current 1=V/R
Power1=Voltage * Current1
Power1=V*V/R
Power1=P
At Bulb 1 and Bulb 2
Total Resistance= R+R=2R
[tex]Current2=\frac{V}{2R}[/tex]
Power2=Voltage * Current2
[tex]Power2=V*\frac{V}{2R} \\Power2=\frac{V^2}{2R} \\Power2=P/2[/tex]
[tex]TotalPower=Power1+Power2\\TotalPower=P+P/2\\TotalPower=\frac{3P}{2}[/tex]
